


The Fruits of Her Labors

by Verchan



Category: Fate/stay night & Related Fandoms
Genre: Bad Ending, Breeding, Creampie, Dubious Consent, F/F, Futanari, Mind Control, Oral Sex, Scent Kink, Sex, Smut, Vaginal Sex
Language: English
Status: Completed
Published: 2019-02-07
Updated: 2019-02-07
Packaged: 2019-10-23 21:26:52
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,584
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17691368
Author URL: https://archiveofourown.org/users/Verchan/pseuds/Verchan
Summary: As the winner of the Fifth Holy Grail War, and corrupted by that very Grail, Caster decides to use her newfound gift to break in Rin.





	The Fruits of Her Labors

The Fifth Holy Grail War was a decisive victory for Servant Caster, the Heroic Spirit known as Medea, along with her Master, Souichirou Kuzuki.  
  
As a witch, Medea was able to harness and tame the dark, corrupted magic within the Holy Grail, and make her wish come true. She was able to reincarnate into the world, bathing in its black mud and drinking of it. However, bathing in such a corruptive, tainted mud brought along side effects as well. Side effects that Medea knew she'd need subjects to relieve herself for. To that end, it was quite fortuitous that she'd managed to win despite sparing the lives of Saber and Rin Tohsaka, two girls who had come to oppose her, and paid for it with their dignity in shambles. After all, with the corruptive mud flowing within her, she was now truly as much of a witch as the legends had painted her.

Surely, it will be indescribably satisfying to break down the girl who had long been a thorn in her side like a chestnut.  
  
...

Trapped in the dark chamber underneath Ryoudou Temple, her arms bound to magical restraints, much in the same way Arturia was bound when she was captured by Medea during the War (with her luscious bottom sticking out as she stood like that), Rin was all alone, unable to save herself or rely on anyone else to save her. Everything was silent as she was left to her lonesome, until suddenly, out of the blue, the pig-tailed girl heard Medea's voice pierce through the air abruptly like a sharp knife.

"Ara... You're still right where I left you, I see. You're not... uncomfortable, are you, girl?" Medea asked Rin with a soft, sinister laugh, walking behind the restrained girl and tracing her gloved hands across Rin's backside, molesting her firm butt as a starter, the skirt practically begging to be ripped off to uncover its treasures underneath.

Rin could hardly understand how did everything go so wrong. In her mind, she constantly repeated the war, over and over again, trying to understand how everything collapsed before her eyes. She'd been training for this war, training for this moment, and somehow she'd made the mistakes, had ended up _here_ , outclassed by someone like Medea and now, who knew what would happen? She couldn't say what was going to happen to her, what Medea intended for her, or where Saber was.

Her skirt rose up as the former Servant touches her, revealing white panties over her smooth fleshy ass, the dark skirt doing little to protect her, but even so, she tries to resist. If she stops fighting, then there's nothing left. She can't give Caster that satisfaction.  
  
"Just fine," Rin snapped, resolving not to show any weakness, to not bend to the witch's games, "Where's Saber? And why do you have me here? The War is over, Caster. Either kill me or let us go, now."  
  
It could never dawn on her, even bent over like this, that there's a more sinister purpose behind it all. After all, the Tohsaka daughter has never thought of the world in these terms, and even now, bent over like this, she can't envision what her fate is to be.

Medea frowned underneath her hood when Rin spoke, continuing to stroke her butt tenderly. "Oh? But little girl, I don't intend to kill you _or_ let you go. The former would be too cruel to you, but the latter would be too cruel to myself. I'd surely miss a darling girl like yourself if you were to leave, ufufu," she said, her mood lightening up slightly as she let out another soft chuckle, slowly trailing around Rin.  
  
"Don't you worry about Saber though. She's doing just fine. Better than she's ever felt, in fact. You'll see her soon enough, I can promise you that," the witch laughed again, stopping in front of Rin, looking down at her with a smirk, "And now that I'm done with her... It's time to get to work on you."

With that, Medea's hand suddenly glowed a dull lavender, focused magical energy enveloping it. Using her thumb and index finger to hold Rin's chin, Medea held the girl in place. Without giving Rin a chance to retort back, she leaned in without another word or moment of hesitation, pressing her lips against Rin's, her tongue intruding inside the teen's mouth.

Medea's taste was sweet, enticingly and overwhelmingly so, or so the mage prodigy would find. All the while, Rin gradually began to have difficulty focusing, as though it became harder to even think, as though the overwhelming sensation of Medea's taste, her smell, her very presence, overtook her. Truthfully, Medea could say the same for Rin. The girl's taste in turn was just as sweet, like strawberries, as did her scent, faintly recalling old perfume. There was no doubt these lips, this supple body, was meant for a man to enjoy, but Medea would be the one to enjoy those rewards.

Once Medea finally pulled away from the kiss, Rin continued to find herself encountering difficulty concentrating on anything. Anything but Medea. Anything but how beautiful she was underneath her hood. Anything but how amazingly pristine her pale skin was. Anything but how good her mere touch felt.  
  
Anything but the desire to give in.  
  
Medea's hand moved from Rin's chin to the top of her head, clutching her head where the witch focused more of her mana in order to influence the girl's mind, as though directly inserting the corruptive magic energy into Rin's brain. "Let yourself go and forget forever, dear Tohsaka. Struggle no more, and give me your love and admiration..." She spoke in a hypnotic tone, with the intent of taking control over Rin's mind.  
  
Rin continued to struggle, to do everything in her power to resist, but it is only here that she realizes how powerless she truly is. Her struggles fade away into the darkness and her eyes begin glowing the same shade of lavender that emanates from Caster's hand, injected into her mind. As her inhibitions began to disappear and drool began to leak out of Rin's mouth like a thirsty child, she focuses all of her undivided attention to Caster, the most beautiful woman she’s ever known, before letting her thoughts try to trail off.

Something finally clicks inside her brain as the mana flows into her barain, and as she blankly gazes upon Caster, she finally speaks in a bland, entranced tone.

“I’m yours, Mistress.”  
  
Who is Rin Tohsaka, the girl found herself wondering, if she isn’t Medea’s? If her body isn’t meant for that beautiful pale skin, for the strong mana ebbing outwards. It feels off, strange, and _right_ all at once to the dear Tohsaka girl, who stares up at Medea with large, eager eyes.

Medea's lips curled into a malevolent smile as she caressed Rin's cheek with her glowing hand, akin to a lover to another, or rather... A mistress and her pet. Breathing triumphantly as Rin easily fell to her wiles, the lavender aura around Medea's hand dissipated. Still, she wasn't done enjoying the spoils of her victory, reveling in her triumph and enjoying her new trophy. To that end, Medea snapped her fingers and with that, the red magical bonds disappeared from Rin's hand, finally freeing her.

As though the bonds were the only things keeping her standing, Rin quickly sank to her knees, panting tiredly, before Medea came to her knees as well, squatting down as though coming face-to-face with the girl, like a dog in Medea's eyes. She grasped Rin's chin again to kiss her once more, the two females enjoying each other's sweet taste as Medea passionately cupped Rin's face with her two hands, deeply kissing her like a lustful beast, having another taste of her sweet tongue, even sweeter and stronger than before now that Caster could taste her own dark magic in Rin. Their tongues tangled together as Rin moans in the kiss involuntarily, sweet and low and needy, her hands coming to cling to Medea's sides.

Eventually, Medea pulled away after a long, heated session of kissing, hot breaths hitting the younger girl's soft skin as she looks directly at Rin from underneath her hood.  
  
"Now then... I've done what you said and freed you from your bonds. You're free to leave now, but... You don't _really_ want to leave anymore, do you? In fact, you don't _ever_ want to leave me ever again, do you?" Medea inquired in a dominant tone, leaning in again to suckle on Rin's neck while her hand groped at Rin's chest, feeling up her young breasts under her red sweater, pleasuring and stimulating her body without mercy, "You want me, don't you? You want me to take you, to make you mine. Go on, tell me how you truly feel, dear Tohsaka..."

Rin is completely at the mercy of Caster, under her complete control, and Medea knew it. For a flash, Rin considered it. She seriously considered breaking free of Medea's control and making a run for it, to beat a hasty retreat, but... She can't. She can't bring herself to. Most pressingly, Rin couldn't will herself to break away from Caster's teasing touch, so close to giving her the ultimate pleasure, but it's just not enough, the fingers too far, covered by red blazer, shirt, the bra underneath. Her thoughts of resistance disappear just as quickly as they materialized, her body unable to go on without more of Caster's deft touch. It didn't take very long for her to come to terms with it; she needed more.

The touch was so close, so intimate, yet too far, and she whined in frustration at the touch, tilting her neck for Medea to have better access. Rin's own hands traveled over Medea's hooded robe, hungrily unclasping it, revealing the woman's pristine skin and beautiful eyes, her pointed ears and luscious hair, as she frantically begged for Caster, the purple glow in her eyes stronger and more vibrant than ever as Medea's mind control grew stronger and stronger.

"Please, please I want to stay with you... w-want you to use me, want you to take me... Please, let me be yours, Caster, let me serve you,” Rin moaned, her voice so close to demonstrating genuine emotion and need, but the hypnotic hold over her restrains her voice.  
  
Rin let out another low groan before moving closer, almost climbing into the Caster's lap, needy and hungry, keeping her gaze focused. "I... want to stay... I want to be yours, _please_ ,” she begged, lacking any sense of dignity that she once had as the heir to the Tohsaka.

"Ara, how adorable... You really are quite a cute little one, aren't you?" Medea said in a deceivingly benign tone without missing a beat, continuing to tenderly kiss and tease the teen's neck, before eventually wrapping her arm around the back of Rin's neck, pulling her close and gazing into her eyes, giving a hypnotic stare.

"You fell so easily to my mind control... Faster than I would have liked personally, though I suppose it's to be expected with someone like you. But that's okay. As long as you've accepted how you truly feel, your desire for me..."  
  
"But don't you worry. I desire you as well, sweet girl. After all, I cannot deny that my body is... drawn to yours..."  
  
From there, Medea gently pushed Rin away a bit to give herself some room, before proceeding to nonchalantly lift up the lower part of her robe, exposing not only her slender, shapely legs and her black panties, but also an erect cock, at least six or seven inches, standing vertically and pressed back against her stomach by her panties. Letting out a soft chuckle, she continued to speak. "When I bathed in the corrupted, black mud of the Holy Grail, drank its thick, rich contents and swallowed it down, my body underwent some... unexpected side effects. But truly, I don't dislike it, even if it's quite big. Wouldn't you agree?"

As Rin catches sight of the beauty before her, eyeing Medea's beautiful glowing skin, her hair, the curve of her panties, the hardness of her cock, the girl is drawn deeper and deeper into Medea's seduction. This lust is beyond anything Rin has ever felt before, and to this end, there is little to no hope for Rin to ever recover her mind. She remains blank faced; all she can do is stare up at Medea, her eyes meeting the witch's and mouth opening, letting out hot breaths as she struggles to think, to even speak.

Tilting her head slightly when Rin seemed to hardly react visibly, Medea decided to take a more assertive approach, theorizing that the girl's active subconscious still existed in some capacity, and still needed to be snuffed out if she intended to keep this girl as the cute slave she could prove to be.  
  
Standing on her two feet now, Medea's exposed cock was at level with Rin's face, the soft, sweet scent of it filling Rin's senses as it slowly throbbed, pre-cum oozing out as the witch thought about the things she would do to the teen. As Rin came face to face with the cock, she can't even compare it to anything; it's a completely new experience for her. All she knows is that it smells so sweet, soft even, like spun sugar, and yet, at the same time, it also... _smelled_. It had a sweet, sugary smell, but at the same time, it held a strong, pungent odor, perhaps more natural of a cock. Caster's own manstink. Caster's own alpha musk. It was almost bizarre for such a delicate looking woman like her to have such a strong, manly smell to her, but either way, Rin found her own mouth watering instinctively, hungry and needy.  
  
"Go on then, girl. Have a taste of my body. Give in to your desires and indulge yourself," Medea said gently, almost lovingly stroking Rin's hair.  
  
Unsteadily, the girl leaned forward, but instead of immediately tasting Caster, she simply buried her face in Caster's full, obscene cum factories, and inhales. She gets a good whiff of Caster's scent, basking in the hypnotizing sugary scent that was mixed with the dominating odor of a man's essence. She can't get enough of the smell, it's driving her crazy! She inhales again, and again, and again. It was hopelessly addictive, and Rin couldn't get enough of it. Her pussy was already soaking wet, her panties practically drenched now, she was so lost in heat. She wanted _more_.

Foregoing simply just smelling Caster's engorged balls, Rin finally stuck out her tongue to have a taste for herself. She dragged her tongue slowly across her tool, from her testicles to her length, lapping up hints of sweat as she made her way up until she reached that sweet pre-cum, darting over her tongue. She sighed in relief and lapped at the tip upon reaching it, but she didn't have the patience with herself to start slowly, so before she knew it, Rin takes the entire cock in her mouth and sucks on it, bobbing her head back and forth, tongue running over the cock and swirling around it. As the former Servant placed a gentle hand on the girl's head, Rin's mind beacme more and more eager to bend, to follow Medea.

Medea sensually bit her lip as she was sucked off, soft moans of pleasure escaping her mouth as she slowly thrust in and out, all the while her hand remained on the girl's head. She reveled in the ecstasy of having her cock be serviced in this manner, but this was ultimately all just foreplay. Caster hungered for more than just this. She wanted to feel her body. She intended to breed Rin Tohsaka, especially considering the girl's fertile, ripe, healthy body.

Eventually, she pulled out of Rin's mouth, edging herself on and keeping herself from cumming until the time was right. Her member was coated with Rin's saliva, but soon, it would be covered in more than just her spit. Continuing to look down at her, Medea spoke in a firm, commanding tone. "Remove your clothes. Strip down and bare your precious body to me. I will promise you this, dear girl, you will learn the true meaning of pleasure. Who knows? Maybe by the time I'm done with you, you'll be _thanking_ me for breeding your body and putting it to use.”

“Y-Yes, Mistress... As you command,” Rin said, her voice taking a submissive tone and her eyes hazed, still glowing that evil shade of purple, overtaking the once striking shade of blue of her eyes. Her hands came to her blouse and unbuttoned the fabric, sensually dropping both shirt and cardigan off her shoulder, slowly free of the fabric. Revealed underneath was smooth white skin and round firm breasts, developed healthily, encased in a red bra. Easily her fingers unsnapped the bra from there, dropping that too to the ground, before she then proceeded to stand up, her skirt sliding off and wet panties dropping along with them and Rin watched her new lover the entire time. Standing in front of Medea, Rin's body was bare before her, nothing more than black hair and pig tails adorning her shape.

Medea smirked darkly as the good little girl did as she was told, stripping down and revealing her nubile, well-rounded body, even going far enough as to lick her lips, her obscene shaft aching and throbbing in anticipation as though ready to take the girl for itself for good, especially as she took in the sight of the girl's bare body, beautifully pale and pristine, like a goddess. But the only goddess here was a witch.  
  
Medea wasted no time in taking her opportunity to kiss the girl again with the intent of putting her further under her spell. The witch's lips captured hers, just as her power captured the young mage's mind, her tongue dominating Rin's as the two of them tasted each other, Rin practically drinking up Medea's sweet, mesmerizing saliva.

Gently, Medea eased Rin down to the ground while kissing her, the cold stone perhaps requiring getting used to if Rin's mind wasn't predisposed with other matters. From there, the witch took Rin's legs and gingerly spread them apart, revealing the most precious part of her body. With her triumphant smirk only growing wider, Medea didn't hesitate. Holding Rin's legs apart and keeping them spread, she thrust her hips forward, her cock slamming inside Rin's young hole without a warning with a _SMACK_ sound, pounding and pounding repeatedly as her meaty balls lightly slap against Rin's exterior as well.

Rin screamed as the meat pole invaded her wet cunny, thrusting into her body with enough force to send shivers throughout her entire body. Her cunt was brutally thrust into but wet enough to take it and as Caster fucked her, the former Master gasped and groaned in response to every powerful thrust, the smacking sounds of wet pussy and hard cock ringing into the air while her own ass jiggled with each smack, her body tightening with each thrust. Rin whimpered, staring up into Caster's eyes, jaw open as though attempting to speak, to say something, but nothing comes out except submissive moans.

Medea bit her lip lightly, grunting softly with every thrust she gave Rin, like a beast, a brute driven by instinct and lust, the kind of creature from her time she hated, but she couldn't deny how amazed she was at how good and tight the girl felt. Her body was truly a treat, above all else. She continued to pound her harder, deeper, faster, unable to hold herself back as she let her lust -- her emotions -- take over and direct her body. At that point, her hips were practically moving on their own, and Medea could only wrap her arms around Rin's body, as though locking herself in with her.  
  
With an ecstatic moan, Medea spoke again between moans. "Ah, so good!~ Your body is perfect! You belong to me! You really are my property!" She exclaimed in the heat of the moment, spurred on by the black mud of the Holy Grail that had influenced her. Her cock made a snug, plugging sound every time it pounded Rin's supple body, heavy balls smacking against her jiggling ass as well.

“Ah! Ah! Nngh!” Rin moaned, yelping like a puppy as she was ravaged by Medea's thick fuckpole. Even if Rin's mind wasn't already Medea's property thanks to the witch's magic, her body had definitely given in to its new mistress, and it felt no shame in voluntarily becoming Medea's. The girl had resigned to her fate as Caster's new cocksleeve; that was all she was good for, that was all she would live for from now on.

The only thing more potent than Medea's thrusts was the pungent smell of sex in the air, penetrating the air more strikingly than even Medea was able to penetrate the former Master; Rin had already drowned and sunk into the pool of lust, but for Medea, as she found herself sinking in as well, she knew she was coming close. Still gripping Rin's hips tightly with each thrust, Medea bit her lip heatedly. “N-Ngh, I'm close! Once I breed you, you will forever be mine without a shadow of a doubt!” She announced dramatically, her thrusts faster and harder than even the witch thought was normally possible for her.

“Y-Yes!~ YES!” Rin screamed, her glowing eyes glazed over, a twisted grin stretching her lips, “Please cum inside me, Mistress! Rin Tohsaka belongs to you! Let me bear your children, Mommy! I LOVE YOU!”

Medea let out a haughty laugh, pleased at just how much she managed to break the girl's mind. “Ahaha, that is precisely what I like to hear! Fine then! Take it all! Take all of my essence!” The former Heroic Spirit exclaimed, and with a beastial roar, practically unfitting of the cool and calculated image she once held as a dark witch, finally orgasmed, her testicles emptying as a squealching sound rang out.

She eagerly came inside Rin, her thick cock milk flowing inside the girl, but instead of a moderately thick, white liquid as one might have expected, Medea's jizz was different. Most strikingly, her cum was black colored, the very same shade as the black mud of the Holy Grail that she had drank when she won the war. More than that, the black-colored cream was thicker than pudding, and came in the form of small lumps inside of unknown material, almost like eggs. There was no doubt about it; Medea's essence was essentially the very same material as the Holy Grail's corruptive, black mud, and now it was flowing without end inside Rin, bulging her slender stomach until she almost looked pregnant.

With a heavy, satisfied groan, Medea finally pulled out like a tight plug, some of her black cum flowing out of Rin's wet pussy. “Mmm... That's quite a good look for you, girl, fufu,” she laughed softly, all the while Rin, moving her hands to push the overflowing cum back inside her wet hole, gave her lover a dizzy, empty smile.

“Thank you, Mistress... It feels _soooo_ good to know my place,” she giggled, eventually licking up some of the black cum off her fingers, reveling in the corruptive taste. Rin could feel herself being overtaken by the power of All the Evils in the World, her hair turning just the slightest whiter and her skin paler, as her personality shifted, more than just into Medea's ideal slave, but as a servant of evil. Yes, that was it. Just as it felt good to be Medea's slave, it felt good to become evil.

Seeing that Medea's cock was still dripping with the black mud, the lumps being pushed out her cock like small beads or pearls, Rin got up to her knees and leaned in, sticking her tongue out and lapping up Medea's mess, dragging her tongue up her length and taking in each lump, swallowing them down. With every lump, every drink of the corrupted mud, that Rin took in, her body continued to change, her veins taking on a black color and becoming very visible underneath her skin.

Putting her hand on Rin's head as the girl serviced her, Medea suddenly tightly gripped Rin's hair and tossed her aside, the slave letting out a soft gasp as she was thrown back to the ground like a piece of trash, not that she minded being treated like this.

“Worry not, girl. You will have plenty samples of All the Evils of the World for the rest of your life. However... I'll be hard at work converting the rest of your classmates. Surely, their bodies are just as ripe for breeding as yours is,” Medea said with a malevolent chuckle, revealing her plans from here as Rin thought of the others; Mitsuzuri, Himuro, Makidera, and Saegusa, among others, and how that meant they'd be joining her very soon. She could hardly wait~

And continuing off from where Medea left off, a familiar voice rang out from behind Rin.

“So in the meantime, I shall fulfill all your needs from here.”

With mild confusion, Rin turned around, only to find the source of the voice; Saber. But... it wasn't quite Saber as she once knew her. She looked like an entirely different being; her hair was lighter than before, an almost deathly white, her skin was even paler than Rin's had become, and her eyes glowed a malevolent golden. Gone was her valiant armor or even the clothes she once wore, given by Rin herself as hand-me-downs, and now she wore a loose-fitting, black gown, and sticking out from that nightgown was a noticeable bulge.

“Of course, who knows? Perhaps in time, you'll grow your own tool and pleasure yourself at your own whim,” Saber Alter smirked, easily noticing Rin hungrily eyeing her bulge.

Medea was a powerful enough witch that the sheer power of her magic managed to override Saber's own Magic Resistance skill, and to that end, used her power to take control of the king's mind, influencing it and bending her to her will. Arturia was now Medea's faithful slave, in multiple senses of the word, and seeing how far she fell, how much she had succumed to and embraced the evil that had overtaken her...

Rin looked forward to falling just as much as Saber had here.

Walking past Rin, swaying her hips seductively with each step, Saber wrapped her arm around Medea, and the two leaned in to passionately kiss each other, locking lips as though knowing it would further arouse Rin, who despite being orgasmed inside was still active. Medea's hand groped at Saber's chest, noticeably bigger and fuller than it was before, before sliding down between her legs and lifting up that part of her dress, exposing her own erect shaft.

“Humph, it appears that it's already as big as mine,” Medea commented, lightly rubbing her still-erect cock against Saber's, moving her arm next around the former king's waist before looking at Rin. “Perhaps... I can spare a few more minutes to play with my lovely subjects.”

With two imposing shafts standing before Rin, she giggled and spread her legs again, ready for another hot session of submission.

 

 

 

 

 

 

 


End file.
